CRISPR may sound like the vegetable drawer in your fridge, but its actually a process that has revolutionized gene editing and holds promise for curing many devastating diseases.

Colloquially known as the use of genetic scissors, the technique has allowed researchers to quickly and efficiently alter plant and animal genes.

Before 2012, if you wanted to change the genome of any organism it was a painstaking, laborious process that could take years if you were lucky and cost tens of thousands of dollar, says Jessica Esseltine, a geneticist at Memorial University in St. Johns.

Now, I can do a CRISPR on Friday, and on Monday, I will have a genetically modified organism in my hands. And it will cost me less than $100.

The discovery won two researchers the Nobel Prize in chemistry earlier this month. Emmanuelle Charpentier and Jennifer Doudna authored the seminal paper on the topic in 2012. It was the first time two women shared the prize, worth almost C$1.5 million

The letters in CRISPR stand for clustered regularly interspaced short palindromic repeats. It usually has the letters Cas9 attached at the end, which is shorthand for CRISPR-associated protein 9, an enzyme thats central to the process.

The term scissors is a metaphor.

It actually involves the use of chemical and biological agents in a controlled environment to alter the structure of DNA, which consists of millions of so-called nucleotides along a twisted, ladder-like strand called a helix.

It is a heady experience, I would say. It feels miraculous to literally watch (cells) change before your eyes." Jessica Esseltine

If you create a double-stranded break in the DNA helix, its kind of catastrophic for a cell, so it tries to fix it immediately, explains Curtis French, another MUN geneticist who works primarily with zebrafish. And when the cell tries to fix it, it can create small mutations, so we can create mutations if we make that double-stranded break.

Or, if we made the break next to a mutation that already exists thats, for example, causing a disease, we can make a break right next to it, and if we give the cell or the animal a little piece of DNA with the right sequence, it can actually incorporate that sequence in when it fixes it.

If this sounds a bit like Bladerunner, keep in mind the sanctioning of any sort of mutant organism is a long way off.

For now, the process shows the most promise in people with blood diseases.

We already treat several blood cancers with stem cell transplants from donors, so I think it could be the easiest if you could take a persons own stem cells and then use CRISPR to correct whatever mutation is causing their cancer and then put it back into that same patient, says Esseltine. That would negate the problem of donor rejection.

She says there are some scientists actually exploring the possibility of growing entire organs in a lab.

But again, its really reaching into science fiction, she says, noting that a Chinese scientist was jailed two years ago for creating mutated embryos.

One thing that isnt fiction, however, is the creation of stem cells.

Long a source of an ethical uproar because they originally had to come from human embryos, stem cells can now be created in a lab from ordinary skin cells.

Its really cool because what you can do is take a piece of skin from any human and you can apply certain pressures to these cells which will cause the cells to spontaneously become stem cells, Esseltine says. They look and behave just like embryonic stem cells, but they have nothing to do with embryos.

Whats more, Esseltine can then put those cells in a petri dish and induce them into becoming almost any other type of cell.

It is a heady experience, I would say. It feels miraculous to literally watch them change before your eyes. And then the heart cells will start to beat in the dish, the brain cells will form connections with each other just like brain cells in our heads do, she says. Its remarkable.

Part of her research involves work with gene mutations that have caused particular grief for Newfoundland families such as arrhythmogenic right ventricular cardiomyopathy (ARVC), sometimes called the Newfoundland curse.

The gene can cause a persons heart to spontaneously stop beating. While the gene can be detected and the carrier equipped with a built-in defibrillator, little is known about the mutation itself.

We actually have no idea what the mutation does at all, she says. Theres a huge gap in knowledge.

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French says MUN researchers are particularly good at detecting gene mutations, but the sheer number of them in any given gene set makes it a little like looking for a needle in a giant haystack.

Once youve found it, fixing it becomes the next challenge.

If they find seven different genes mutated in a patient that has a certain disease, we can try to mutate those genes in a fish to see which one actually causes the disease, he says.

Twitter: @pjackson_nl

Peter Jackson is a Local Journalism Initiative reporter covering health care for The Telegram.


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